The subject matter disclosed herein relates to refrigeration systems. More specifically, the subject matter disclosed herein relates to refrigeration of trucks, trailers and containers utilized to store and ship cargo.
A typical refrigerated cargo truck or refrigerated truck trailer, such as those utilized to transport a cargo via sea, rail or road, is a truck or trailer having a cargo compartment, modified to include a refrigeration unit located at one end of the truck or trailer. The refrigeration unit includes a compressor, condenser, expansion valve and evaporator serially connected by refrigerant lines in a closed refrigerant circuit in accord with known refrigerant vapor compression cycles. A power unit, including an engine, drives the compressor of the refrigeration unit, and is typically diesel powered, or in other applications natural gas powered. In many truck/trailer transport refrigeration systems, the compressor is driven by the engine shaft either through a belt drive or by a mechanical shaft-to-shaft link. In other systems, the engine drives a generator that generates electrical power, which in turn drives the compressor.
Manufacturers and operators of fleets of refrigerated trucks and refrigerated truck trailers desire to maximize operational efficiency of not only the refrigeration unit, but of the truck or tractor trailer system as a whole.